#include <bits/stdc++.h>
using namespace std;

#define int int64_t
#define endl "\n"
using PII = pair<int, int>;
using TII = tuple<int, int, int>;
#define FOR(i, a, b) for (int i = (int)(a); i <= (int)(b); i++)
#define FOR2(i, a, b, c) for (int i = (int)(a); i <= (int)(b); i += c)
#define FORD(i, b, a) for (int i = (int)(a); i >= (int)(b); i--)
#define FORD2(i, b, a, c) for (int i = (int)(a); i >= (int)(b); i -= c)
#define BSI basic_string<int>
#define BSPI basic_string<PII>
#define ALL(a) a.begin(), a.end()
#define RALL(a) a.rbegin(), a.rend()
#define VI vector<int>
#define VII vector<vector<int>>
#define VPII vector<PII>
#define lowbit(x) ((x)&(-x))
#define RE return;
#define RET return true;
#define REF return false;
#define Yes cout << "Yes" << endl;
#define YES cout << "YES" << endl;
#define No cout << "No" << endl;
#define NO cout << "NO" << endl;
#define pb push_back
#define fi first
#define se second
#define sz size()
constexpr int N = 2e5 + 10;
constexpr int mod = 998244353;

int __FAST_IO__ = [](){
    ios::sync_with_stdio(0), cin.tie(0);
    cout.tie(0);
    cout << fixed << setprecision(12);
    return 0;
}();

string s;

void solve() {
    getline(cin,s);

    int a=0,b=0,c=0,t=0;
    char opa;

    bool ca=0,cb=0,cc=0;

    for(auto x:s){
        if(x!='+'&&x!='-'&&x!='*'&&x!='/'&&x!='?'&&x!='='&&(x<'0'||x>'9'))continue;
        if(isdigit(x)||x=='?'){
            if(x=='?'){
                continue;
            }
            if(t==0){
                a=a*10+(x-'0');
                ca=1;
            }else if(t==1){
                b=b*10+(x-'0');
                cb=1;
            }else if(t==2){
                c=c*10+(x-'0');
                cc=1;
            }
        }else if(x!='='){
            opa=x;
            t++;
        }else if(x=='='){
            t++;
        }
    }
    
    if(!ca){
        if(opa=='+'){
            cout<<fixed<<setprecision(2)<<(double)c-b<<endl;
        }else if(opa=='-'){
            cout<<fixed<<setprecision(2)<<(double)c+b<<endl;
        }else if(opa=='*'){
            cout<<fixed<<setprecision(2)<<(double)c/(double)b<<endl;
        }else{
            cout<<fixed<<setprecision(2)<<(double)c*b<<endl;
        }
    }else if(!cb){
        if(opa=='+'){
            cout<<fixed<<setprecision(2)<<(double)c-a<<endl;
        }else if(opa=='-'){
            cout<<fixed<<setprecision(2)<<(double)a-c<<endl;
        }else if(opa=='*'){
            cout<<fixed<<setprecision(2)<<(double)c/(double)a<<endl;
        }else{
            cout<<fixed<<setprecision(2)<<(double)a/(double)c<<endl;
        }
    }else if(!cc){
        if(opa=='+'){
            cout<<fixed<<setprecision(2)<<(double)a+b<<endl;
        }else if(opa=='-'){
            cout<<fixed<<setprecision(2)<<(double)a-b<<endl;
        }else if(opa=='*'){
            cout<<fixed<<setprecision(2)<<(double)a*b<<endl;
        }else{
            cout<<fixed<<setprecision(2)<<(double)a/(double)b<<endl;
        }
    }

}

signed main() {
    int Task = 1;
    for (; Task; Task--) {
        solve();
    }
    return 0;
}